I bought an mp4 player a while back, I had it for about 1 week and thought it was brilliant. Cheaper than an Ipod and does exactly the same thing plus more. However..
When you play videos the picture seems to go weird and you have to tilt the player in different directions to see it properly. This is really annoying. Also, when putting files e.g. mp3 files on to the player, most of the time it says corrupt and it needs reformating. Then everything has been deleted, this is really annoying too because it takes long enough putting all the files on. After about 5 days, the sound went really funny, I opened it up to find the headphones socket had completely feel out of place and needed soldering back into place! I just left it there. Bought an Ipod nano which is well worth the money!
My opinon on the mp4 player.. cheap piece of plastic made in hong kong and awful quality!